Bittium an nov. sp.? Plate 1 L 1 -L 2, M 1 -M 2 Santa Maria material examined. Maximum height 4.5 mm, width 1.8 mm. DBUA-F 488-2 (29), Ponta do Castelo, Santa Maria Island, Azores, Touril Complex, Lower Pliocene. Description. Shell small, turriculate, with tall, slender spire, apical angle about 33°. Protoconch not preserved. Teleoconch of nine weakly convex whorls, initially slightly cyrtoconoid in profile, separated by a narrow, moderately impressed, undulating suture. Sculpture of broad rounded, slightly opisthocline to orthocline ribs, about seven on penultimate whorl, extending between suture and weakly crenulating abapical suture. Last two whorls with one or two varices per whorl. Spiral sculpture weak, on early whorls three broad flattened cords separated by narrow grooves. Spiral sculpture weakens on fourth whorl, subobsolete on last three whorls. Axial sculpture predominant, without tubercles produced at intersections. Last whorl convex, moderately constricted at base, bearing a spiral cord at the level of the insertion of the outer lip, a peribasal cord of similar strength, and three weaker basal cords. Aperture ovate, features obscured by matrix. Discussion. Bittium an nov. sp. is clearly similar to B. miradouroense nov. sp. but differs in having a wider apical angle (33° vs. 23°) and fewer axial ribs (7 vs. 12). The character of the spiral sculpture seems to be similar, slightly stronger on early whorls and both species have two spiral cords delimiting the base. However, comparison is hampered by the form of preservation: the specimen of Bittium an nov. sp. is somewhat decorticated, whereas the fossils of B. miradouroense are calcitic pseudomorphs. Nevertheless, the wider apical angle and the small number of ribs seem to be constant characters separating the two. As discussed under B. miradouroense, the shells of these two species are not particularly similar to any other Neogene or extant European species. Distribution. Lower Pliocene: Atlantic, Santa Maria Island, Azores (this paper).

Published as part of Sacchetti, Claudia, Landau, Bernard & Ávila, Sérgio P., 2023, The Lower Pliocene marine gastropods of Santa Maria Island, Azores: Taxonomy and palaeobiogeographic implications, pp. 1-150 in Zootaxa 5295 (1) on pages 32-33, DOI: 10.11646/zootaxa.5295.1.1, http://zenodo.org/record/7965273